In medical institutions, liquid transport is often needed, such as an infusion, transfusion, artificial dialysis, blood collection, etc. Tubes are used to transport various types of liquids. A connector controls the tubes, merging multiple types of liquids or blocking the flow as needed. Said connector is set halfway on the tube, and a mixer for mixing in other medicine solutions is attached to the tube, and various other applications are adopted for the tube. For example, the connector may have the function of a switching valve, and the valve is used as a 3-way valve that can control the feeding of liquids from multiple flow channels. The connector is attached at the terminal of a medicine solution tube, and it usually blocks the feeding of the liquid from said medicine solution tube, and it is opened only when needed for feeding the liquid. That is, the connector is used as a normally OFF valve.
Usually, the connector has a housing that forms a flow channel space for the flow of the medicine solution or other liquid. The housing has a connecting port connected to the flow channel. The flow channel is connected through the connecting port to the flow channel space for the flow of the medicine solution. Also, in the housing, an opening portion is formed for feeding the liquid to be fed from the outside. The Luer syringe portion is inserted in the opening portion, and the medicine solution or the like is fed through the opening portion into the flow channel space.
However, for the connector of an opened system with nothing attached to the opening portion, when the Luer syringe portion is not inserted while the flow channel space is normally connected to the outside, the medicine solution may spill out of the flow channel space. Also, bacteria may reproduce in the portion attached to the medicine solution near the opening portion. Consequently, in the recent years, a normally closed type valve member is attached to the opening portion, and, when the Luer syringe portion is not inserted, the opening portion is blocked liquid tight. Such connector of the blocked system is often in use.
The connector of the blocked system usually has a slit formed on the valve member attached to the opening portion (see Japanese Kokai Patent Application No. 2003 159336 and Japanese Kokai Patent Application No. Hei 8[1996]206230). Then, in the normal state (when the Luer syringe portion is not inserted, and no liquid is fed), this slit is closed. On the other hand, when liquid feeding is performed, the Luer syringe portion is inserted in the slit. Then, the slit is opened, and the Luer syringe portion is exposed to the flow channel space inside the housing. As the liquid to be fed is injected in this state, the liquid is injected into the flow channel space, and the liquid is fed. After end of feeding of the liquid, the Luer syringe portion is pulled out of the slit. As a result, the slit is once again closed, and the opening portion is blocked.
For the valve member used in the conventional connector of the blocked system, said through slit is formed, and the Luer syringe portion is inserted via said slit. Consequently, as the slit is opened/closed repeatedly, the slit portion degrades. When the slit portion degrades, the slit cannot be well closed. In this state, the advantage of the connector of the blocked system cannot be well displayed, and the liquid may leak out of the flow channel space. Also, bacteria may reproduce at the periphery of the slit.